Black holes are one of the most fascinating and mysterious phenomena in the universe. Formed from the remnants of massive stars that have undergone gravitational collapse, black holes possess gravitational forces so strong that nothing, not even light, can escape their grasp. This unique characteristic gives them their name and makes them invisible to traditional observational methods.

Astronomers study black holes indirectly by observing the effects they have on nearby matter. For instance, when a star orbits a black hole, it can emit X-rays as it is pulled in, providing clues to the black hole's presence and properties. The study of supermassive black holes, which reside at the centers of galaxies, offers insights into galaxy formation and evolution. Recent advancements, including the Event Horizon Telescope, have allowed scientists to capture images of black holes’ event horizons, deepening our understanding of these enigmatic entities and their role in the cosmos.